News / Science & Technology

Scientists Discover 1 Planet Orbiting 2 Stars

Artist's conception of planet (dark circle) orbiting two suns
Artist's conception of planet (dark circle) orbiting two suns

Astronomers say they have discovered a planet that orbits around a pair of stars.  It is the first time a so-called circumbinary system has been detected.

Movie fans might be familiar with the score of "Star Wars, Episode IV, A New Hope," the blockbuster movie from 1977.  Luke Skywalker stands on his stark home planet Tatooine.  As he gazes pensively into the distance toward a pinkish sky, an orange sun descends toward the horizon, with a smaller white sun following close behind.  

Well, move over, Tatooine, says John Knoll of Industrial Light and Magic, which created the special effects for the "Star Wars" films.

"Again and again we see that the science is stranger and cooler than the fiction," Knoll said.

Make way for reality -- Kepler-16b, the first planet known to definitively orbit two stars.  That makes it a circumbinary planet.

A research team, led by scientist Laurance Doyle, used data from the Kepler space telescope to make the discovery.

Kepler-16b is 200 light years from Earth.  It is about the mass of Saturn, and it is half-rock and half-gas.  It is in orbit around two stars that are smaller than our Sun, and those two stars are in what Doyle calls "an eccentric orbit" around each other.   

"Well, this is an example of another planetary system.  A completely different type that we've never seen before.  And so that's why everybody is making a big deal of it.  Nobody's ever seen a place like this before. . . with one exception.  I seem to remember seeing a place like this about 30 years ago in a galaxy far, far away...," Doyle said.

And that would, of course, be the "Star Wars" fictional planet Tatooine.  

Researchers describe this newly discovered Kepler system as a rather graceful one.  The two stars twirl around each other every 41 days.  The planet orbits in a circle around both of the stars every 229 days.

But how did researchers find it?

The Kepler space telescope measures changes in the brightness of more than 150,000 stars as it searches for transiting planets.  
All three bodies in this system orbit in the same plane, and that is why the telescope observed the various planetary and stellar eclipses.  The dimming in brightness at irregular intervals indicated the stars were in different positions in their orbit each time they were passed by the third body, planet Kepler-16b.

"We have two stars dancing around each other, and in our line of sight, they eclipse each other, and then we have this exquisite little pirouette of the planet going around both of them, and we get to see how big the planet is as well," Doyle said.

Scientists were able to deduce the planet's mass by the gravitational tug on the stars, as measured by changes in their eclipse times.

The goal of the Kepler mission is to find other Earth-like planets that could support life.  Doyle says this planet is not habitable.

"The bright star is kind of orange.  It's more orange than the sun.  And the little star is red.  It's very red.  So that's an example of another thing to be considered when you talk about habitable planets is, 'what is the color of the light?'  Is it color that plants can use to photosynthesize, and so on?," Doyle said.

Doyle says researchers do not yet know the rotation period, so they do not yet know the planet's sunrises and sunsets.  But, he said, they would be dynamic because of the stars' eccentric orbits.  Sometimes the red star would set first, sometimes the orange one.  Sometimes they would set together.  

"You'd have, of course, two shadows, because the orange star would cast a shadow, but the red star would fill it in because it's at a different angular point in the sky, and vice versa.  So, if you want to tell the time by sundial, you'd need calculus, you know," Doyle said.

The findings are described in a study published in the September 16th issue of the journal Science.

You May Like

Uganda Court Annuls Anti-Gay Law

Court says law was passed in parliament without enough members present for a full quorum More

Multimedia Thailand Makes Efforts to Improve Conditions for Migrant Laborers

In Thailand, its not uncommon for parents to bring their children to work; one company, in-collaboration with other organizations, address safety concerns More

In Indonesia, Jihad Video Raises Concern

Video calls on Indonesians to join Islamic State of Iraq and the Levant, ISIL More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
In Thailand, Some Efforts to Improve Conditions For Migrant Laborersi
X
Steve Herman
August 01, 2014 6:22 PM
Thailand has been facing increasing international scrutiny as a hub of human trafficking and slave labor. Some of the kingdom’s companies are striving to improve working conditions, especially for the millions of migrant laborers from surrounding countries. VOA Correspondent Steve Herman in Bangkok takes a look at one initiative for children at construction sites
Video

Video In Thailand, Some Efforts to Improve Conditions For Migrant Laborers

Thailand has been facing increasing international scrutiny as a hub of human trafficking and slave labor. Some of the kingdom’s companies are striving to improve working conditions, especially for the millions of migrant laborers from surrounding countries. VOA Correspondent Steve Herman in Bangkok takes a look at one initiative for children at construction sites
Video

Video Public Raises its Voice on Power Plant Pollution

In the United States, proposed rules to cut pollution from the nation’s 600 coal-fired power plants are generating a heated debate. The U.S. Environmental Protection Agency, charged with writing and implementing the plan, has already received 300,000 written comments. As VOA’s Rosanne Skirble reports, another 1,600 people are lining up this week at EPA headquarters and at satellite offices around the country to give their testimony in person.
Video

Video Information War Rages Alongside Real One in Ukraine

The downing of the Malaysian airliner two weeks ago, and allegations that Russians are shelling Ukrainian troops across the border, have moved the information war swirling around the Ukrainian conflict to a new level. VOA's Al Pessin reports from Kyiv.
Video

Video When Fighting Eases, Gazans Line Up at Bakeries

When there is a lull in the conflict in Gaza, residents who have been hunkered down in their apartments rush out to stock up on food and other necessities. Probably the most important destination is the local bakery. VOA’s Scott Bobb reports from Gaza City.
Video

Video China Investigates Powerful Former Security Chief

The public in China is welcoming the Communist Party's decision to investigate one of the country's once most powerful politicians, former domestic security chief Zhou Yongkang. Analysts say the move by President Xi Jinping is not only an effort to win more support for the party, but an essential step to furthering much needed economic reforms and removing those who would stand in the way of change. VOA's Bill Ide has more from Beijing.
Video

Video US-Funded Program Offers Honduran Children Alternative to Illegal Immigration

President Obama and Central American leaders recently agreed to come up with a plan to address poverty and crime in the region that is fueling the surge of young migrants trying to illegally enter the United States. VOA’s Brian Padden looks at one such program in Honduras - funded in part by the United States - which gives street kids not only food and safety but a chance for a better life without, crossing the border.
Video

Video 'Fab Lab' Igniting Revolution in Kenya

The University of Nairobi’s Science and Technology Park is banking on 3-D prototyping to spark a manufacturing revolution in the country. Lenny Ruvaga has more for from Nairobi's so-called “FabLab” for VOA.
Video

Video Immigrant Influx on Texas Border Heats Up Political Debate

Immigrants from Central America continue to cross the U.S.-Mexico border in south Texas, seeking asylum in the United States, as officials grapple with ways to deal with the problem and provide shelter for thousands of minors among the illegal border crossers. As VOA's Greg Flakus reports from Houston, the issue is complicated by internal U.S. politics and U.S. relations with the troubled nations that immigrants are fleeing.

AppleAndroid